Justin Bieber Denies Giving Car To Sean Kingston

Kingston began the charade in front of Boa this weekend ... when he rolled up to the steak joint in JB's chromed-out car and told photogs Justin had given it to him as a gift ... as a perk of their friendship.

But sources close to the The Biebs tell TMZ Kingston's pants are COMPLETELY on fire -- truth is, Sean asked Justin if he could BORROW the car to go to dinner since Bieber is on tour ... and Justin obliged.